American and Mexican officials say they want a renegotiated deal by December.

This week the influential US Chamber of Commerce warned it was time to “ring alarm bells” over the Nafta talks.

The business lobby group said there were “several poison pill proposals” put on the table by the US that could tank the renegotiations.

Those include US demands to adjust the rules of origin, which would increase the percentage of the content of car parts and other materials that would come from Nafta countries in order for a good to qualify as duty free – a specific concern for the North American auto industry.

‘We disagree vehemently’

The US and Canadian leaders also discussed the Bombardier-Boeing trade dispute.